Running imagemagick convert with ProcessBuilder

Question

I want to run the following command on Windows command prompt:

convert -density 50 -pointsize 70 -font Arial label:"Text with spaces" output.gif

This command uses imagemagick and makes a gif file with the text "Text with spaces" and saves it to output.gif

This works nicely straight from Windows 7 command prompt. Now, I want to run this command from a Java application of mine. Consider:

private void runConvert()
{
    try
    {
        ProcessBuilder pb = new ProcessBuilder("convert","-density","50","-pointsize","70"
        ,"font","Arial","label:","\"Text with spaces\"","output.gif");

        pb.redirectErrorStream(true);
        Process process = pb.start();
        BufferedReader inStreamReader = new BufferedReader(newInputStreamReader(process.getInputStream()));

        while(inStreamReader.readLine() != null){
            System.out.println(inStreamer.readLine());
        }

     } catch (Exception e){
         e.printStackTrace();
     }
}

Problem is, this makes convert echo:

convert.exe: no decode delegate for this image format `' @ error/constitue.c/ReadImage/501

If I try to use runConvert function with a text parameter that has no spaces, like "BurgerKing" it works like a charm. How can I fix it for multi spaces parameters?

I recommend to use [im4java](http://im4java.sourceforge.net/) It is reliable interface library to execute ImageMagick operations. — , Jul 16 '14 at 08:43
You are missing a '-' in front of your "font" argument. It explains your error if that is not a typo. — dlemstra, Jul 16 '14 at 09:03

score 0 · Answer 1 · answered Jul 16 '14 at 10:56

0

You should specify label: and "Text with spaces" as a single argument:

ProcessBuilder pb = new ProcessBuilder("convert","-density","50","-pointsize",
"70","-font","Arial","label:\"Text with spaces\"","output.gif");

answered Jul 16 '14 at 10:56

dlemstra

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Have you tried this? convert echos nothing but there's no file output. – user1555863 Jul 16 '14 at 11:18
Did you check the working directory of your application for the file output.gif? Your file might be written to a different location on your disk then what you are expecting. – dlemstra Jul 16 '14 at 12:22
Checked. Also changed it into a known directory by changing `output.gif` to `c:\\testings\\output.gif`. – user1555863 Jul 16 '14 at 12:37
Did you also check the output from process.getErrorStream? – dlemstra Jul 16 '14 at 12:54

Running imagemagick convert with ProcessBuilder

1 Answers1